A guide to understanding the science of Covid-19 and its implications

The pandemic that has currently held our world in a state of paralysis has pushed the information machine into overdrive. We are at the receiving end of a battery of continual governmental briefings, news bulletins, in-depth scientific articles, statistics on incidences and deaths, informed-speculation and pure conjecture. Opinions, theories, paranoia and facts are ubiquitous and ever-permeating. How do we sort through the information that we need to draw solutions that are pertinent only to the population in which one resides? Even when we do manage to sieve and retain only the significant morsels of information, how do we translate high-brow biochemistry and government policy and apply it to our social mores and practices?

The magnitude of this challenge positively correlates with the size of the affected population. This is the case that South Asian countries are facing. The hurdle is not just in distilling information into intelligible bullet points, e.g. like the government's measures to curb virus transmission across the population, but to make direct correlations of these points to the particular communal activities that are fundamental to South Asian society. The dimensions of the challenge increase when we factor in the diversity within individual South Asian countries. It would be fair to say that no other region in the world has the particular characteristics that this subcontinent has: the population size and density, multitudes of ethnicities, languages, the socio-economic classes, religions, deep-rooted traditions and sectarian biases, among other facets. The situation is hampered by excessive misinformation flowing through South Asian phones about the unfounded curative properties of fruits, spices and practices on defeating the coronavirus.

So, what is the coronavirus? The name "coronavirus" actually refers to a family of related viruses of which the virus underlying COVID-19 disease is one of seven (Guo et al., 2020). It has a 79.5% genetic similarity to the Severe Acute Respiratory Syndrome coronavirus (SARS) (Kampf et al. 2020; van Doremalen et al.2020) that infected populations around 2002. Since it belongs to the sub-family of coronavirus named SARS-CoV, it is also referred to as SARS-CoV-2 (Guo et al., 2020). Viruses can contain either DNA or RNA as their genetic material. Coronaviruses are RNA viruses, where the RNA is encapsulated by a wall of proteins that form a structure called the nucleocapsid. This nucleocapsid is covered by a viral envelope from which protruding proteins, called spikes, attach to a prey host cell (Seah et al., 2020, Andersen et al., 2020). It is thought COVID-19 (aka SARS-CoV-2) targets cells the same way as SARS-CoV, i.e. the virus spike attaches to the protein Angiotensin-Converting Enzyme 2 (ACE2). ACE2 is essentially the doorknob that the virus uses to enter the host cell. It is usually found on the surface of lung cells, which is why the symptoms for COVID infection are characterized by respiratory problems (Seah et al., 2020). This symptom also accounts for the demand for ventilators. News outlets reported most recently New York's dire need of ventilators, for which China met the call and provided 1000; while India has been making concerted effort to be self-sufficient and scaled its production of toaster-sized ventilators to aid COVID-19 patients.

A word of caution however needs to be flagged to avoid obsessive engagements with ventilators in resource-poor countries. While ventilators have been found useful in treating common forms of pneumonia, evidence is not so encouraging in case of COVID-19. Several small studies from the U.S., China and Europe reveal that most coronavirus patients who end up on ventilators go on to die (see NPR news report). The news report quoted Dr. Tiffany Osborn, a critical care specialist at Washington University: "the ventilator itself can do damage to the lung tissue based on how much pressure is required to help oxygen get processed by the lungs". Furthermore, the report stated that "coronavirus patients often need dangerously high levels of both pressure and oxygen because their lungs have so much inflammation. Another risk from being on a ventilator is that the tube carrying air and extra oxygen to the lungs provides a pathway for dangerous germs. Many ventilated patients get a new lung infection, a problem known as ventilator-associated pneumonia."

While cures for COVID-19 are being researched, and symptoms are being treated, the focus of all governments have been to try and stem the transmission. Even though the source of the virus is uncertain (the link to bats, although the most probable, is still speculative (Wan et al., 2020)), the human-to-human transmission of COVID-19 is akin to an unseen forest fire. "Social distancing" (recently dubbed 'physical distancing' in the South Asian context) is the only way to slow transmission and is being proselytized globally. Countries like the United Kingdom and Canada with far smaller populations than India, Pakistan or Bangladesh have used police enforcement to prevent people from gathering. But, how would this work in South Asia? Even if people did isolate themselves as per the WHO instructions, it marginalizes farmers and migrant workers. Farmers are left with limited opportunity to sell their goods, and their produce perish (see Reuters article). The same applies to fisheries and livestock farmers. The latter, as part of the food sector, will probably receive a financial package from the Government of Bangladesh to keep them afloat (see Dhaka Tribune article). City-dwellers will only become aware of the dependency on the unseen half that provide all the essential and non- essential elements on South Asian dining tables during the long-drawn out lockdowns.

South Asia still has a strong agricultural core. It might benefit the situation to allow farmers to hand their goods to government-issued/regulated transport trucks so the goods can be brought to the city, delivered to specific drop-off points at regular geographic intervals within the city. Vendors will not have to traverse across the city to pick up the produce and are localized to their area from which they sell goods. If each consumer provides a list of items to auto-rickshaw, van (with gear or batteries), or rickshaw driver, the latter can deliver the goods back to the consumer. Immobilizing vendors to a locality and keeping rickshaw, van and auto- rickshaw drivers employed within pre-set perimeters, could limit virus transmission between vendors, and from vendors to consumers to households. Simpler said than done for there are many vendors and only so much space in densely populated cities like Dhaka and Mumbai. Yet, with wide coverage of mobile network, home-grown ideas on ICT applications may permit such delivery network.

Another issue that South Asian societies will be facing is the high mortality rate if the virus transmission is left unregulated. Western Europe has been tackling high mortalities at the Winter/Spring cusp. Spain resorted to temporarily housing bodies in an ice rink due to the cold temperature prior to burial or cremation. South Asia has already been hit by very warm temperatures. We ask whether it is possible that storing a large number of bodies in a hot climate, before they can be buried/cremated, may pose a health risk? For the Ebola epidemic the World Health Organization website stated that "Infection of the Ebola virus can occur from touching the bodies of those who have died from Ebola virus disease (EVD)", since Ebola is transmitted via bodily fluids, and that trained teams would handle burials so that they could be performed safely. However, infection from COVID-19 mortalities are not expected to occur in the way they do from Ebola-related deaths. The World Health Organization released a report (publication dated March 24th 2020) stating, "there is no evidence of persons having become infected from exposure to the bodies of persons who died from COVID-19", and that those "who have died from COVID-19 can be buried or cremated". The WHO have indicated proper procedures, such as: the use of protective personal equipment (PPE; such as gloves and masks) when handling the COVID-19 deceased; and not touching or kissing departed persons; and steps to disinfect the surface where the body was kept (see WHO's March 24th 2020 Interim Guidance), since coronaviruses and specifically COVID-19 can stay on various surfaces (such as stainless steel and plastic) for up to 48-72 hours (Kampf et al., 2020, van Doremalen et al., 2020). Most recently, news outlets reported that New York City's Hart Island has been the site of mass burials of wooden coffins, with workers taking precautions and wearing hazmat suits. Once the COVID-19 peak hits South Asia and mortalities surge (especially if physical/social distancing is not enforced) it seems questionable that countries will be fully equipped with enough morgues, to keep bodies cool enough in the hot weather until there are enough burial plots and cremation slots available, as well as enough trained personnel (to prepare the body and at the sites of burial/cremation), or even PPE to deal with the fatalities. Most importantly, there is a need to plan all those well ahead accounting for the rainy season.

While the frequent and proper handwashing techniques have been expounded and practiced, the issues of water consumption and waste management must also be addressed. While coronavirus transmission in general occurs through the act of coughing, sneezing or coming into contact with viral droplets on surfaces, the question of how susceptible water supplies are to the virus may be of concern to many. The coronavirus is considered low-risk to water supplies (see WHO's Guidelines for drinking-water quality; WHO's March 19th 2020 Interim Guidance). This should be a note of relief for South Asian governments since drinkable water is a precious resource indeed for these nations. However, measures have still been put in place as a precaution to ensure water sources are safe for consumption. WHO recommends "centralized water treatment methods that use filtration and disinfection should inactivate the COVID-19 virus" (WHO's March 19th 2020 Interim Guidance). However, in areas where there is no facility for centralized water treatment, they suggest that "a number of household water treatment technologies are effective in removing or destroying viruses, including boiling or using high-performing ultrafiltration or nanomembrane filters, solar irradiation and, in non- turbid waters, UV irradiation and appropriately dosed free chlorine" (WHO's March 19th 2020 Interim Guidance). Boiling water has been a tried and true process that generations have relied on, and it is the convenient golden standard that must be relied upon yet again in very rural areas.

The routes of transmission have already been established in this article (inhalation and contact) however, faeco-oral transmission must be addressed. In this part of the world where proper sanitation for all citizens is yet to be achieved and open defecation is still observed in some areas, is it possible that the COVID-19 cycles through humans and re-enter a community in the same manner as cholera? One research group claimed that they were able to detect live COVID-19 virus in fecal samples from patients hospitalized between January 1st to February 17th 2020 from Hubei and Shandong provinces indicating that possible transmission can occur (Wang et al., 2020). In another article that is yet to be published, but has already garnered attention as a news piece in Nature (Mallapaty, 2020), a group in the Netherlands found that they were able to detect COVID-19 in sewage (Medema et al., 2020). Most importantly, this group proposes that testing wastewater might be a very early indicator for the presence of COVID-19 in the community, well before the symptoms appear. The WHO's stance is that there "is no evidence that the COVID-19 virus has been transmitted via sewerage systems with or without wastewater treatment" (WHO's March 19th 2020 Interim Guidance). There is still not enough to draw conclusions on faeco-oral transmission in areas of large developing populace and open defecation. However, in regions that lack proper sanitation and wastewater treatment, we can only hope that raw human waste doesn't compound the ongoing problem.

After lockdown measures are lifted how will governments prevent the floodgates of infection from rapidly opening and re-infecting the masses? Staggering the lifting of lockdown measures within different quadrants of the city may slow the number of people moving through the city at a time. However, South Asian countries have a high-dependency across socio- economic classes, be it: taxi, bus and auto-rickshaw and private drivers, or the house help, grocery vendors, postal office clerks/couriers, food service providers, small business owners, students all the way up the chain to teachers, bankers, scientists, large business owners and government officials. It would be difficult to disentangle societal inter-dependency as the economy ramps up, but who should be allowed to enter the streets first? Furthermore, how will this be regulated?

At the moment it isn't certain that an adaptive immune response occurs to COVID-19, or if there is a chance of relapse. Severe cases of COVID-19 may leave patients with lung damage (Shi et al., 2020), which is a point of concern to all developing nations. We can hope that South Asian economies will accelerate again. Yet, one cannot rule out the possibility that the cities will draw smog curtains around themselves again, factory work in closed stuffy quarters may resume, and even labour-intensive work of the agriculture sector may resurface and expose the sensitized respiratory tracts of afflicted-individuals post-pandemic. All those speculations make the case for vaccination. However, developing vaccines for COVID-19 is still at an experimental stage, and respective governments will have to make hard choices on the use of drugs. Currently the anti-malarial drug hydroxycholorquine is being tested in a clinical trial using 3000 test subjects through a joint effort by the McGill University, University of Minnesota, University of Alberta and the University of Manitoba (see Edmonton Journal article). India is one of the largest producers of this drug and has agreed to supply it to Nepal, Bhutan and Bangladesh, along with paracetamol to aid in curbing COVID-19 (see The Economic Times article). While there are hopes around the drug use, the efficacy of treating COVID-19 still needs to be established through the aforementioned clinical trials. If the drug is deemed efficacious, South Asia will hopefully be able to swiftly provide treatment through mutual dependence and exchanges, without having to wait for the interventions of the Western nations.

The people and governments of the South Asian sub-continent must brace themselves for the peak and subsequent casualties and mortalities when the coronavirus ravages these nations. Better comprehension, firm decisions with calculated risks by the governments in the region may reduce those adverse effects.

References

ANDERSEN, K. G., RAMBAUT, A., LIPKIN, W. I., HOLMES, E. C. & GARRY, R. F. 2020. The proximal origin of SARS-CoV-2. Nature Medicine.

GUO, Y.-R., CAO, Q.-D., HONG, Z.-S., TAN, Y.-Y., CHEN, S.-D., JIN, H.-J., TAN, K.-S., WANG, D.-Y. & YAN, Y. 2020. The origin, transmission and clinical therapies on coronavirus disease 2019 (COVID-19) outbreak – an update on the status. Military Medical Research, 7, 11.

KAMPF, G., TODT, D., PFAENDER, S. & STEINMANN, E. 2020. Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents. The Journal of hospital infection, 104, 246-251.

MALLAPATY, S. 2020. How sewage could reveal true scale of coronavirus outbreak. Nature, 580, 176-177.

MEDEMA, G., HEIJNEN, L., ELSINGA, G., ITALIAANDER, R. & BROUWER, A. 2020. Presence of SARS-Coronavirus-2 in sewage. medRxiv, 2020.03.29.20045880.

SEAH, I., SU, X. & LINGAM, G. 2020. Revisiting the dangers of the coronavirus in the ophthalmology practice. Eye.

SHI, Y., WANG, Y., SHAO, C., HUANG, J., GAN, J., HUANG, X., BUCCI, E., PIACENTINI, M., IPPOLITO, G. & MELINO, G. 2020. COVID-19 infection: the perspectives on immune responses. Cell Death & Differentiation.

VAN DOREMALEN, N., BUSHMAKER, T., MORRIS, D. H., HOLBROOK, M. G., GAMBLE, A., WILLIAMSON, B. N., TAMIN, A., HARCOURT, J. L., THORNBURG, N. J., GERBER, S. I., LLOYD-SMITH, J. O., DE WIT, E. & MUNSTER, V. J. 2020. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. N Engl J Med.

WAN, Y., SHANG, J., GRAHAM, R., BARIC, R. S. & LI, F. 2020. Receptor Recognition by the Novel Coronavirus from Wuhan: an Analysis Based on Decade-Long Structural Studies of SARS Coronavirus. Journal of Virology, 94, e00127-20.

WANG, W., XU, Y., GAO, R., LU, R., HAN, K., WU, G. & TAN, W. 2020. Detection of SARS-CoV-2 in Different Types of Clinical Specimens. Jama.

Interim Guidance: Infection Prevention and Control for the safe management of a dead body in the context of COVID-19. World Health Organization. March 24 2020. (https://apps.who.int/iris/bitstream/handle/10665/331538/WHO-COVID-19-lPC...)

Interim Guidance: Water, sanitation, hygiene, and waste management for the COVID-19 virus. World Health Organization. March 19 2020. (https://apps.who.int/iris/bitstream/handle/10665/331499/WHO-2019-nCoV-IP...)

Guidelines for drinking-water quality, fourth edition, incorporating the first addendum. Geneva: World Health Organization; 2017 (http://apps.who.int/iris/bitstream/10665/254637/1/9 789241549950-eng.pdf, accessed 3 March 2020). 

World Health Organisation: Emergencies preparedness, response; Safe and dignified burials (http://www9.who.int/csr/disease/ebola/training/safe-burials/en/)

Dr Sudipa Chatterjee is an independent writer and cell biologist. She volunteered to prepare this brief for common readers at the request of Economic Research Group.